The most common of these palpable shapes which disease is supposed to assume, is that of “humors,” as they are termed in popular language. The disappearance of a “humor” is the _effect_ quite as often as it is the cause of disease; and yet it is very difficult to make people understand this—they persist in thinking it always to be a cause. So also, if a patient, on recovering from any sickness, has some eruption appear upon the skin, it is taken for granted, that it was this “humor” that has been inside all the time, which has caused all the sickness; and now that it has ceased to play its pranks among the internal organs, and has come out, the patient as a consequence gets well. It never enters their minds, that the eruption may be simply a result of that revival of the energies of the system, which is consequent upon its escape from the depressing influence of disease. This idea of the palpable shape of disease gives rise to the popular error, which is so prevalent, in regard to the necessity of getting out _all_ the eruption in such diseases, as scarlet fever, measles, &c. The idea is that there is a certain amount in the system, and that this must _all_ be brought out upon the skin, or the patient will suffer some bad consequences from this retention of morbid matter. This notion is entirely erroneous. The eruption in such cases is not the coming out or throwing off of diseased matter contained in the system, but it is merely one of a succession of processes in the natural course of the disease. It is indeed necessary that this process should be well executed, and if the natural energies of the system do not prove adequate, they should be assisted by medicine. But ordinarily they are adequate; and in comparatively very few cases, is there any need of any assistance from art in bringing out the eruption. Most of the dosing so common in scarlet fever and in measles, for this purpose, is worse than useless—it aggravates the symptoms, multiplying and inflaming the eruption beyond the necessities of the case, and it increases the complications which are incidental to it. Death is often the consequence of such officious interference with nature’s regular processes.